http://www.ck12.org Chapter 3. Chemical Interactions
FIGURE 3.7
the group than from lithium (Li) at the top of the group (see theFigure3.7). In bigger atoms, valence electrons are
farther from the nucleus. As a result, the force of attraction between the valence electrons and the nucleus is weaker.
Q:What do you think happens when an atom gains an electron and becomes a negative ion?
A:Energy is released when an atom gains an electron. Halogens release the most energy when they form ions. As a
result, they are very reactive elements.
Summary
- An ionic bond is the force of attraction that holds together positive and negative ions. It forms when atoms of
a metallic element give up electrons to atoms of a nonmetallic element. - Ionic bonds form only between metals and nonmetals. That’s because metals “want” to give up electrons, and
nonmetals “want” to gain electrons. - It takes energy to remove valence electrons from an atom and form a positive ion. Energy is released when an
atom gains valence electrons and forms a negative ion.
Vocabulary
- ionic bond: Force of attraction that holds together positive and negative ions; forms when atoms of a metal
give up valence electrons to atoms of a nonmetal.
Explore More
Fill in the ionic bonding worksheet at the following URL.
http://moodle.usevs.org/pluginfile.php/1231/mod_resource/content/0/Ionic%20Bonding%20Worksheet-1.pdf
Review
- What is an ionic bond? How does it form?
- Why do metals lose electrons and nonmetals gain electrons in the formation of ionic bonds?
- Atoms of lithium (Li) and cesium (Cs) both lose electrons and become positive ions when they from ionic
bonds. Which type of atom requires more energy to become an ion? Why?